I have a small doubt in this, as per the star join startagy it will create hash tables. If our fact table is very huge and our temp DB can’t take up this amount of data into hash table how does it manage the query.

SELECT itm.userreviewid AS itemid,
itm.reviewitem AS title,
itm.imgpath AS imgpath,
‘Barkspider’ AS [Source],
reviews.numratings,
reviews.avgrating,
5 AS ratingmax,
” AS itempath,
” AS identifier,
‘barspider-user-review.png’ AS logo,
Isnull(0, 0) AS fromprice,
Isnull(0, 0) AS toprice,
reviews.totrating,
Newid() AS ‘NewID’,
‘a’ AS bssort
FROM barkspiderblog.dbo.userreviews itm WITH (nolock)
JOIN (SELECT COUNT(1) AS numratings,
AVG(rating) AS avgrating,
SUM(rating) AS totrating,
reviewitem
FROM barkspiderblog.dbo.userreviews WITH (nolock)
GROUP BY reviewitem) reviews
ON Lower(itm.reviewitem) = Lower(reviews.reviewitem)
WHERE ( ( ( itm.reviewitemid IS NULL
OR itm.reviewitemid = 0 )
AND itm.parentid IS NOT NULL )
OR ( itm.reviewitemid IS NOT NULL
AND itm.reviewitemid = itm.userreviewid ) )
AND itm.reviewitem LIKE ‘%tv%’
AND itm.userreviewid IN (SELECT userreviewid
FROM (SELECT Rank() OVER (PARTITION BY
reviewitem
ORDER
BY createdon ASC) AS
r1,
userreviewid
FROM barkspiderblog.dbo.userreviews
WHERE reviewitem LIKE ‘%tv%’) tab
WHERE tab.r1 = 1)
UNION ALL
SELECT itm.itemid,
itm.title,
itm.imgpath,
src.DESCRIPTION AS [Source],
reviews.numratings,
reviews.avgrating,
src.ratingmax,
itm.itempath,
itm.identifier,
src.logo,
fpr.fromprice,
fpr.toprice,
reviews.totrating,
Newid() AS ‘NewID’,
‘b’ AS bssort
FROM items itm WITH (nolock)
JOIN sources src WITH (nolock)
ON itm.sourceid = src.sourceid
JOIN (SELECT COUNT(1) AS numratings,
AVG(rating) AS avgrating,
SUM(rating) AS totrating,
itemid
FROM reviews WITH (nolock)
GROUP BY itemid) reviews
ON itm.itemid = reviews.itemid
LEFT OUTER JOIN fetchitemprice fpr WITH (nolock)
ON itm.itemid = fpr.itemid
WHERE title LIKE ‘%tv%’
UNION ALL
SELECT itm.itemid,
itm.title,
itm.imgpath,
‘Barkspider’ AS [Source],
reviews.numratings,
reviews.avgrating,
5 AS ratingmax,
itm.itempath,
itm. identifier,
‘barspider-user-review.png’ AS logo,
0 AS fromprice,
0 AS toprice,
reviews.totrating,
Newid() AS newid,
‘a’ AS bssort
FROM items itm WITH (nolock)
JOIN sources src WITH (nolock)
ON itm.sourceid = src.sourceid
JOIN (SELECT COUNT(1) AS numratings,
AVG(rating) AS avgrating,
SUM(rating) AS totrating,
reviewitemid,
reviewitem
FROM barkspiderblog.dbo.userreviews WITH (nolock)
GROUP BY reviewitem,
reviewitemid) reviews
ON itm.itemid = reviews.reviewitemid
LEFT OUTER JOIN fetchitemprice fpr WITH (nolock)
ON itm.itemid = fpr.itemid
WHERE itm.itemid IN (SELECT ur1.reviewitemid
FROM barkspiderblog.dbo.userreviews ur1 WITH (nolock)
WHERE ur1.parentid IS NULL)
AND title LIKE ‘%tv%’
ORDER BY bssort,
Newid()